I Have Had Extreme Itching From My Legs Up To

I have had extreme itching from my legs up to my arm pits. It started about 3 months ago with just my shins and slowly has spread to the rest of my body. I have been to the dermatologist and they prescribed a steroid cream which has not caused the itching to subside. I just wondered if there is anything that could alleviate the constant discomfort?